Objects

Objects

Pre-build objects are available in the APMonitor language to facilitate flowsheets of chemical processing equipment. Objects are defined in the Objects ... End Objects section of the model file. New instances of an object are defined by declaring a new object name equal to the parent object type.

new_child = parent_object

Object Library

The object library consists of chemical processing equipment such as feed streams, reactors, pumps, mixers, flash columns, vessels, and distillation stages. It also includes other elements that support distributed control system emulation such as a LAG and a PID controller.

Thermo objects

Thermo objects access data from the underlying thermodynamic database. There are over 1700 compounds accessible in the database. To reduce the size of the APMonitor executable, only some of the more common compounds are currently incorporated. Additional compounds can be easily added but require a rebuild of the executable.

Temperature Independent Property Data

Temperature independent property data do not vary with temperature. They are defined as constants for each of the species declared in the Compounds ... End Compounds section of the model. If the Compounds ... End Compounds section is missing, all available compounds are included in the model.

thermo_mw

Molecular Weight

kg/kmol

thermo_tc

Critical Temperature

K

thermo_pc

Critical Pressure

Pa

thermo_vc

Critical Volume

m^3/kmol

thermo_ccf

Crit Compress Factor

unitless

thermo_mp

Melting Point

K

thermo_tpt

Triple Pt Temperature

K

thermo_tpp

Triple Pt Pressure

Pa

thermo_nbp

Normal Boiling Point

K

thermo_lmv

Liq Molar Volume

m^3/kmol

thermo_ighf

IG Heat of Formation

J/kmol

thermo_iggf

IG Gibbs of Formation

J/kmol

thermo_igae

IG Absolute Entropy

J/kmol*K

thermo_shf

Std Heat of Formation

J/kmol

thermo_sgf

Std Gibbs of Formation

J/kmol

thermo_sae

Std Absolute Entropy

J/kmol*K

thermo_hfmp

Heat Fusion at Melt Pt

J/kmol

thermo_snhc

Std Net Heat of Comb

J/kmol

thermo_af

Acentric Factor

unitless

thermo_rg

Radius of Gyration

m

thermo_sp

Solubility Parameter

(J/m^3)^0.5

thermo_dm

Dipole Moment

c*m

thermo_r

van der Waals Volume

m^3/kmol

thermo_q

van der Waals Area

m^2

thermo_ri

Refractive Index

unitless

thermo_fp

Flash Point

K

thermo_lfl

Lower Flammability Limit

K

thermo_ufl

Upper Flammability Limit

K

thermo_lflt

Lower Flamm Limit Temp

K

thermo_uflt

Upper Flamm Limit Temp

K

thermo_ait

Auto Ignition Temp

K

Temperature Dependent Property Data

The temperature dependent thermo objects produce values based on a specified temperature. When a temperature dependent property object is declared, a new temperature variable will be created. This variable can be adjusted or linked to an existing temperature of interest.